I inoculated NDV containing AAF into 9 day old SPF egg. After 72 hours of incubation, the AAF was harvested. Amplification of M and FPCS gene showed a positive PCR product. But, I am not able detect NP gene by PCR. Is it because of less NP transcripts?
And, the M and FPCS that I am detecting, will it be from the residual inoculum?